Are you talking about reloading your scene or code during development?
Indeed Playcanvas provides hot reloading which is pretty cool, to be able to update/change your code and see the effects in the game world without having to restart your app. You can read more about it here:
To reload your scene, setting for example all objects to their initial state, that can’t be done automatically. You will have to use hot reloading to reset their state your self in code, which isn’t so hard to do, but you have to take care of doing this in code for each entity/script in play.